/Engine/Source/Runtime/SlateCore/Public/Application/SlateApplicationBase.h
Get a list of all top-level windows in the application, excluding virtual windows.
An array of all current top-level SWindows.
const [TArray](API\Runtime\Core\Containers\TArray)< [TSharedRef](API\Runtime\Core\Templates\TSharedRef)< [SWindow](API\Runtime\SlateCore\Widgets\SWindow) > > GetTopLevelWindows() const